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3rd Gen fork bottom Allen bolt


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Not the usual problem of not being able to undo it, had no trouble with that. It’s getting it done back up that I’ve messed up.

First leg went back together perfectly. The second one, I was doing the bolt up with an Allen key and not really paying attention, it felt like I was tightening up ok and I went to nip it up before getting the torque wrench when…… spin, spin, spin. 
Now one of two things has happened; 1. The bolts fine, it’s the damper rod assembly that’s spinning or 2. I’ve cross threaded the bolt and have now stripped a thread, hopefully on the bolt but possibly the rod.

Scenario 1. Ive tried assembling the leg completely but the bolt spins. Ive pulled the rod, I’ve pushed the rod, pulled the leg, pushed the leg. The bolt spins or rather it gets “tight” then loosens off. What do I do?

Scenario 2. Help. What do I do? Drill it out?

Looking forward to an easy solution!🤞

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On my VF, I took an old broomstick. Cut bits of wood of at one end to make it more pointy. Tapped it in gently into the stanchion till it gripped. Hokd the stick firm abd used electric impact driver....

 

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The bolt is M8, using an 8mm drill in the Allen bolt head carefully drill through the bolt head until the head comes off and the assembly drops out

 

 

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Unfortunately, a drill bit may very well spin, too...

 

So, before you get all medieval on it, try using an impact ratchet/rattle gun and a long Allen key to loosen it (again).  The problem is that the lower valve body you're screwing into (or out of) is not anchored to anything within the fork, so it can spin within the cartridge.  The impact-type wrench usually manages to jolt it free when conventional tools just spin.  Be careful with the Allen key, however, as the OEM M8 cap screw is the "shallow head" type, so it is easier to round it out than with a normal screw: Make sure it is fully seated before trying to rattle it out.  If you don't have an (air) rattle gun, I suggest you take the fork over to the (back) door of a friendly bike shop and ask them to undo it for you.

 

To help a little with developing friction between the lower valve body and the cartridge it's spinning in, you can PULL the forks apart (but this is still unlikely to solve the problem).

 

Race-Tech does not have any tool that I can see which is designed to grip the cartridge on a RWU fork.  Anyway, there's no way they could have anything for this particular problem, given that the thing which is spinning is not attached to the cartridge anyway.  Yes, you can jam the cartridge against the wall of the lower fork tube with a beveled dowel, but again, it isn't the cartridge which is spinning...

 

Ciao,

 

JZH

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Thanks so much for all your replies.

I made a wooden tool to jam the cartridge, which it did, but the bolt kept spinning even when pulling the damper rod & stanchion. So I gave up and went to a mechanic, he seemed very confident he’d be able to get it out “…you just need to shock it out with a rattle gun”. 
He came back after 5 minutes, “The bolt’s just spinning. It’s like the valve is spinning because something is jamming the bolt, I need your help.”

So with the fork fully extended and the stanchion held in a vice he pulled on the lower leg while I pulled on the damper rod then gave short bursts with an impact driver (the kind you use to fix screws into wood rather than the rattle gun) and YES it came out!

On inspection he said there was a piece of thread locker jammed in the threads of the valve body which was preventing the bolt from screwing in fully which was causing the valve body to turn instead. After carefully re-tapping the thread  he was able to assemble the fork without any more drama.

He said DON’T use any thread locking compound on these bolts, it’s not necessary and whoever had used it on this one had used far too much.

 

Well I know who did it, it was a Honda main dealer around 15 years ago when I had a leaking seal replaced while on a touring holiday.

 

Now to get the front end back together before starting on replacing the rear shock. Fingers crossed for that going smoothly.

 

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  • 3 weeks later...

I feel your pain here.  I’m currently dealing with this on my 6th gens fork.  It just spins and spins, can’t even retighten it or anything.  I used an electric impact driver from the start but with no resistance on the bolt there is no actual rattling going on.  I tried heating it, pulling the rod for tension, pushing it for compression, jamming a piece of wood down the stanchion, and even flushing it out with kerosene to remove the oil and increase the friction.  I know it is that caked up threadlock on the end of the bolt doing this but nothing has worked and the fork has now been at a shop for the past week.  I’ve never felt so defeated by such a dumb issue.
 

 I just left the bolt in on the other fork and changed the oil from the top.  I feel like it will irk me knowing it’s there waiting to be another huge headache.  I’ve never felt so envious of bikes with modern suspensions 🤮

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7 hours ago, Spandrel said:

I feel your pain here.  I’m currently dealing with this on my 6th gens fork.  It just spins and spins, can’t even retighten it or anything.  I used an electric impact driver from the start but with no resistance on the bolt there is no actual rattling going on.  I tried heating it, pulling the rod for tension, pushing it for compression, jamming a piece of wood down the stanchion, and even flushing it out with kerosene to remove the oil and increase the friction.  I know it is that caked up threadlock on the end of the bolt doing this but nothing has worked and the fork has now been at a shop for the past week.  I’ve never felt so defeated by such a dumb issue.
 

 I just left the bolt in on the other fork and changed the oil from the top.  I feel like it will irk me knowing it’s there waiting to be another huge headache.  I’ve never felt so envious of bikes with modern suspensions 🤮

Sounds like you're doing all of the obvious stuff. As a suggestion (and just that, no personal experience) is it possible to jam something between the bolt and forkleg to stop it spinning, and drill the head off then?

 

The problem with these forks is that the damper base that the bolt threads into is just held in the bottom of the damper tube by a circlip, and can spin freely (as you found). Pulling up on the damper rod pulls the base against the circlip and adds friction (but maybe not enough). 

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8 hours ago, Spandrel said:

I feel your pain here.  I’m currently dealing with this on my 6th gens fork.  It just spins and spins, can’t even retighten it or anything.  I used an electric impact driver from the start but with no resistance on the bolt there is no actual rattling going on.  I tried heating it, pulling the rod for tension, pushing it for compression, jamming a piece of wood down the stanchion, and even flushing it out with kerosene to remove the oil and increase the friction.  I know it is that caked up threadlock on the end of the bolt doing this but nothing has worked and the fork has now been at a shop for the past week.  I’ve never felt so defeated by such a dumb issue.
 

 I just left the bolt in on the other fork and changed the oil from the top.  I feel like it will irk me knowing it’s there waiting to be another huge headache.  I’ve never felt so envious of bikes with modern suspensions 🤮

 

The air-powered rattle guns seem to be the best at this task, but I haven't personally used the technique often enough to see any statistical difference. 

 

As Terry said, the only non-destructive alternative is to drill the bolt out, as far as I can see.

 

Ciao,

 

JZH

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Loctite SF768 is the solvent for the locking fluid, try soaking the fork bottom in that for a while, although I’m told acetone works on some types 

 

If pushing the damper rod doesn’t stop it turning I’d try getting someone strong to pull on it and use an 8mm drill (the cobalt ones piss through the bolts) and carefully drill the head down the Allen key hole until the head comes off

 

 

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Drill it out & replace with new. Every bad one I've done was seized in the alloy, once the head was drilled off the fork popped apart & the threaded remains unscrewed by hand. 

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